'''
Created on 2012-4-23

@author: nzhao
'''
import numpy as np

SpinDictionary={'E': {'SpinValue':                  0.5,
                      'GyromagneticRatio':          -1.760859794 * 10**11,
                      'RelativeGyromagneticRatio':  -2.61793125 * 10**3
                      },
                'C': {'SpinValue':                  0.5,
                      'GyromagneticRatio':          6.726149871 * 10**7,
                      'RelativeGyromagneticRatio':  1.0
                      }
                }

Mu0      = 4 * np.pi * 10**-7;
Angstrom = 1.0 * 10**-10;
Hbar     = 1.054571596 * 10**-34;

GammaUnit = SpinDictionary['C']['GyromagneticRatio']
SpinSpinInteraction = Mu0 / 4.0 / np.pi * GammaUnit**2 / Angstrom**3 * Hbar / 1000.0